Manage SNMP extensions

Dynatrace provides you with a framework that you can use to extend your observability into data acquired directly from your SNMP-monitored devices. To this end, Dynatrace enables you to bring SNMP data into Dynatrace at scale and within the context of all other data.

You can also extend your insights into data related to SNMP traps issued in your infrastructure.

First, check Dynatrace Hub to see if your device is covered by an existing extension. If it isn't, you can build your own Dynatrace SNMP extension to cover your SNMP device.

Before you begin

1. Decide which SNMP will provide data for the extension. Dynatrace Extensions 2.0 framework supports SNMP v2c and v3. Depending on the SNMP version, prepare the necessary authentication details.
2. Designate an ActiveGate group or groups that will remotely connect to your SNMP devices to pull data. All ActiveGates in each designated group need to be able to connect to your SNMP devices.
3. Learn hardware requirements for an ActiveGate performing SNMP monitoring.

Manage SNMP extensions

Dynatrace Hub provides a unified workflow to enable and manage extensions that will ingest SNMP data into your Dynatrace environment.

Required permission: Change monitoring settings

1. From the Dynatrace menu, go to Dynatrace Hub.
2. Search for snmp to find an SNMP or SNMP traps extension.
3. Select Add to environment. This creates the environment configuration for your extension, thus enabling the extension in your environment.
4. Select Add monitoring configuration.

After that, perform the following steps.

ActiveGate group

Define devices

Advanced properties

Activate extension

ActiveGate group

Select the ActiveGate group to determine which ActivGates will run the extension. When done, select Next step.

Define devices

Select Add device to define the devices from which you want to pull data and provide the device connection details:

• IP address or device name
• Port
• SNMP version and related authentication details. Authentication details passed to Dynatrace when activating monitoring configuration are obfuscated and it's impossible to retrieve them.

Advanced properties optional

SNMP extensions only

Select Define to configure optional advanced properties:

• Timeout in seconds
  The maximum time (in seconds) to wait for an SNMP query to return data. Default = 2 seconds.
• Retries
  The maximum number of retries for a query if it fails (total time for a query is timeoutSecs x retries). Default = 3 retries.
• Max repetitions
  Can be used to limit the amount of data returned for a single query and might in turn increase the number of requests sent to the device until all required data is collected. Default = 50 repetitions.
• Max OIDs per query
  Number of OIDs that can be queried in one SNMP request. Default = 60 OIDs. For most extensions, you don't need to change it. For the F5 BIG-IP LTM extension, we recommend that you set it to 5.

SNMP Traps extensions only

Select Add varbinding rule to configure variable binding trimming:

• Variable binding (OID) prefix
  The part of the OID that is matched for trimming.
• Number of octets trimmed
  The number of octets at the end of the OID that you want to trim.

When done, select Next step

Activate extension

Provide final configuration details.

• Description
  Text explaining details of this particular monitoring configuration. When troubleshooting monitoring, this can give your teams details of this particular monitoring configuration.
• Feature sets
  In highly segmented networks, feature sets can reflect the segments of your environment. You can use them to limit your monitoring to particular segments. Feature sets are predefined for each extension. For SNMP traps extensions, select the Events feature set to enable the forwarding of trap messages as log events.
• Variables
  Some extensions offer variables with which you can pass custom strings to your extension and report them in the environment, for example, as your dimension. Some extensions contain the ext.activationtag variable that is passed as a dimension to your monitoring configuration. You can use it to associate the reported metrics with a particular version of your monitoring configuration.

When done, select Activate.

Monitoring configuration as JSON

The extension activation wizard contains a dynamically updated JSON payload with your monitoring configuration. See Extensions 2.0 lifecycle to learn how to use it to activate an extension using the Dynatrace API.

Custom MIB files

Management Information Base (MIB) is the database managing the entities in a network identified by OIDs. MIB provides a source of additional information related to OIDs declared in your extension.

ActiveGate comes with a default set of MIB files. If some of the OIDs used in the extension are not available in the default MIB files, you can add your own MIB file to the ActiveGate running SNMP extensions.

Your custom MIB files are then used by all the SNMP and SNMP Traps extensions running on this ActiveGate.

Place your custom MIB files in the mib-files-custom directory:

• Linux: /var/lib/dynatrace/remotepluginmodule/agent/conf/userdata/mib-files-custom/
• Windows: C:\%PROGRAMDATA%\dynatrace\remotepluginmodule\agent\conf\userdata\mib-files-custom\

The files stored in the mib-files-custom directory are preserved between updates.